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  1. #1
    Join Date
    Nov 2008
    Posts
    4

    Upstairs too cold...

    I'm living in a 22 year old two story custom built home on a wooded lot in the Pacific NW. The The square footage is 3680. I purchased the house a year ago and am still learning the HVAC system. Apparently, the original owner was a HVAC specialist. Here's what I know about my system. I have two heat pumps, one is original the other was replaced in 2001. The back up is a Tagagi Flash hot water heater installed this year. The downstairs comprises approximately half the square footage and has an open floor plan with a large two story entry (about 18 feet high), an open living room/dining room and kitchen/family room combo. The downstairs has four return air vents and eleven heating/cooling vents. The downstairs thermostat is in a middle hallway and is set to 69 degrees during the day which makes the main floor comfortable. At night the thermostat is programed to drop to 65 degrees. There are two stairways front and back that lead up to three bedrooms, two baths and a large bonus room over the garage. There are a total of five return air vents and nine heating/cooling vents upstairs. The upstairs thermostat is located in a narrow hallway that separates the bonus room from the three bedroom/two bath area. There is also a door that can be closed that separates the bonus room from the rest of the upstairs. During the day the upstairs thermostat is set to 69 degrees and at night it's set to 64 degrees. Given all the venting and two independent heating/cooling systems in this house I would expect the house to be more comfortable. The master bedroom and master bathrrom are freezing and the bonus room over the garage is cool while the rest of the upstairs is comfortable, especially the hallway. I suspect the location of the large master suite and the number of windows (original double pane metal) are not helping my situation either. I have three exteriors walls, four windows and a glass door to a deck. I have had measurements of an eight degree termperature difference between the master bedrrom and the hallway where the thermostat is located. Currently all vents are open upstairs and down. I'm willing to close off the two bedrooms that aren't being used but the ceiling heating/cooling vents are very difficult to close as there are a square comerical style that have louvers that don't close all the way down. Also the noise of air pushing through a slightly closed ceiling vent is very noticable and annoying. During the day I keep the double doors to the master suite open. It helps a little bit but it is still too cool to be comfortable. At night the doors to the master suite must remain closed due my neighbor's bright outside lights which probably also contributes to the room being cold. I'm looking for any suggestions as to how to improve the comfort of the master suite and bonus room without spending a fortune. Last year my heating bills were incredibly high so I'm trying to find ways to reduce my costs of maintaing a comfortable upstairs. Any ideas?
    Thanks,
    Jon

  2. #2
    Join Date
    Feb 2003
    Posts
    1,996

    There's not enough info

    but I assume each floor is a zone. You might want to have the thermostat moved to the
    master bedroom and have the the vents re-balanced. You might have dampers in the attic that could be adjusted.

    How is the gas instant HW heater used? Is this a hydro air set up with a coil in the air hander. Is the upstairs air hander in the attic? What's high your electric or gas bill?

  3. #3
    Join Date
    Nov 2008
    Posts
    4

    Upstairs too Cold

    John,
    There are two completely independent heating and cooling systems. One heat pump handles the upstairs, the other handles the downstairs. Is that what you mean by zones? Moving the thermostat into the master suite might be an option. I suspect that it would increase the heating costs though... Don't know what re-balancing vents mean. Is that where you close off some rooms and keep others fully open? I'm not sure what to look for in regards to dampers in the attic. What do they look like? The Takagi instant water heater is used as a backup system when the outside temperature goes below 40 degress. The water heats up and air is forced over the coils and distributed throughout the house by a fan. There are two air handlers, one for downstairs and a second one in the attic.
    Re: so far I've seen a gas and electric total was around $450 with it most likely going even higher in the coldest months.
    Thanks,
    Jon

  4. #4
    Join Date
    Aug 2003
    Location
    Fort Worth, TX
    Posts
    11,345
    By how you describe the master bedroom, the amount of heat it continually loses to the cold exterior air is insufficiently replaced by your heating system. You have two remedies for this problem:
    • Reduce heat loss from the room to outdoors
    • Increase amount of heat available to the room to replace what is being lost to the outdoors
    The first option is more preferable for more satisfying, sustainable results, but generally has higher initial cost. The second involves knowing how much heat the room is losing on "design" cold days for your area, and then ensuring enough heated air is delivered to the room to offset the heat loss for such a day.

    If you reduce the heat lost to outdoors, you reduce the amount of heated air necessary to make up for what is lost to outdoors. With due diligence, the amount of heat loss could be stemmed to where no increase of heat output delivered to the room would be necessary.

    Stemming heat loss from the master bedroom will involve assessing how effective the windows are at reducing heat transfer...if they are the original 22 year old double pane jobs, they might not have thermally improved frames, the argon gas between the panes might have leaked out (often indicated by the glass appearing cloudy or smoky), or the window's weatherstripping no longer seals well, or all of the above plus others. If the glass door to the deck is a sliding glass door, one of the old single pane aluminum frame types, those are awful heat bleeders.

    Look at the ceiling of your master bedroom. Is it punctured with "can lights" (recessed lighting), and supply and return air vents? If so, you're losing air to your attic if those penetrations are not sealed properly.

    Bonus rooms over a garage can be problematic, since somehow insulating the floor between the garage and the bonus room is often, oddly, overlooked. If the bonus room gets cold, it will draw warmer air from adjacent spaces.

    Being a two story structure with a tall entry spanning both floors, you may have what is called "stack effect" going on, whereby holes in the ceiling to the attic allowing heated air to escape draws cold air into the lower floors through air leaks in the walls. It is hard to keep a multi-story house comfortable when it can't sufficiently hold in the air you pay to heat. It's comparable to having the best heating system in the world, but leaving a window on the lowest floor wide open. Self defeating. You cannot adequately control air until you first contain it.
    • Electricity makes refrigeration happen.
    • Refrigeration makes the HVAC psychrometric process happen.
    • HVAC pyschrometrics is what makes indoor human comfort happen...IF the ducts AND the building envelope cooperate.


    A building is NOT beautiful unless it is also comfortable.

  5. #5
    Join Date
    Dec 2007
    Location
    Cedar Grove, Wi-Sheboygan
    Posts
    1,582
    Well stated !!! Bravo sir !!!

  6. #6
    Join Date
    Feb 2003
    Posts
    1,996

    before the tagaki

    You must of had a real gas boiler in there capable of making 180 degree water.
    Flow is restricted through an instant water heater. You might need a higher capacity pump on the loop now. Does each coil have it's own pump or just a single pump with zone valves. Instamt water heaters are OK for radiant systems, but if your coil needed the full 180 degree water to heat the space, you might need a real boiler.

  7. #7
    Join Date
    Jul 2004
    Location
    Massachusetts
    Posts
    6,837
    It's all pure guess work, whether we'er inn your house looking at the problem or sitting at our computers guessing. It's still all guess work. The only true way to solve your problem is to start with a load analysis, room-by-room. That will give you a lot of information, such as how much heat is needed in each zone as well as in each room. Once you know that, you can compare the results to the existing equipment and ducts. Properly sized? If so, perhaps you have a service issue; under charged, short cycling, dampers not moving, t-stat cycles out of whack, etc. Not properly sized, then there's the beginning of a solution; get right-sized. Generally relocating a thermostat to overcome an imbalance is a losing proposition. If the rooms are too cool and the t-stat is statisfied, then you need to set it to a higher temperature and you'll get warmer in the cold area. Yes, the location where the t-stat is will also get warmer but with an imbalance, if you move the t-stat to the cooler room, that old location is going to get warmer just the same. So relocating to overcome imbalance doesn't work. If the t-stat is being affected by another heat source of sunlight, that's a different story. That's a good reason to relocate it away from a lamp or heat outlet.

    Do the Manual 'J' load analysis, then give us some model numbers on the equipment. We'll also need some duct measurements, supply outlet measurements and lengths of run. Then we could begin to really do justice to a long distance troubleshooting effort.
    If YOU want change, YOU have to first change.

    If you are waiting for the 'other guy' to change first, just remember, you're the 'other guy's' other guy. To continue to expect real change when you keep acting the same way as always, is folly. Won't happen. Real change will only happen when a majority of the people change the way they vote!

  8. #8
    Join Date
    Nov 2008
    Posts
    4

    Upstairs too cold

    John,
    Yes, before the Tagaki, we had a 22 year old gas boiler. However, it was super inefficient so we replaced it with an instant hot water heater. I know there is a pump on the loop but I'm not certain of its specs in reference to the coils. I'll do some research on the Tagagki Instant hot water heater.
    Thanks,
    Jon

  9. #9
    Join Date
    Nov 2008
    Posts
    4
    Skippedover,
    Thanks for your input. There is a lot information to gather here. I suspect the analysis is needed to get to the root of our problem. It could well be that we are at the end of the natural life cycle of this system, no matter how well built it was for its time. I want to make darn sure I have done everything I can before I shell out tons of money for anything new. Our system hasn't been serviced since we moved in a year ago. Problem is, it's a commerical grade system in a residential home. Three different HVAC companies have scratched their heads when they see what we have. I'll keep looking for someone.
    Thanks,
    Jon

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